Percussive tool for scaling tubes.



F. GILMAN & G. P. GLEMENTS.

PBRGUSSIVB TooL FOR SGALING TUBES.

4 APPL-NATION FILED NOV.12, 1910.

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FRANK GILMAN .AND GEORGE FREDRICK CLEMENTS, 0F SMETHWIC'K, ENGLAND,ASSIGNORS T0 BOILER SCALERS LIMITED, OF BIRMINGHAM, ENGLAND.

PERCUSSIVE TOOL FOR SCALIJSI'Gr TUBES.

Speciication of Letters Patent.

Patented Nov. 14, 1911'.

To all whom it may concern: A

Be it known that we, FRANK GILMAN and GEORGE FREDRICK CLEMENTS, subjectsof His Majesty the King of 'Great Britain and Ireland, residing,respectively, at High Park Road, Smethwick, in the county of Stafford,England, and at 82 Trafalgar road, Smethwick aforesaid, engineers, haveinvented new and useful Improvements in- Percussive Tools for ScalingTubes, of which the followingV is a specification.

This invention consists of the herein described improvements inpercussive tube scaling tools ofthat type which consists'ot a pneumaticor otheriuid pressure hammer adapted to enter the tube to be scaled andhaving thev fore end of the shank of the hammer piston protrudingthrough the cylinder and made coned or inclined to actflpon a number ofinternally inclined chisel like or blunt parts which are arranged aroundbrate radially and which receive the rapid vibratory blows of the hammerpiston which, acting through said inclines, cause t-he said chisel likeparts to chip the scale from the interior of the tube, or cause the saidblunt parts to vibrate against the interior of the tube and thus jar thescale ofi"v the outside.

of the same. Percussive tube scaling tools of this type are adapted tobe worked with compressed air or with steam or other fluid underpressure and are employed for removing the scale from the interior ofthe tubes of water tube boilers condensers steam econolnizers and thelike, and also by rapid internal blows to remove the scale from theoutside of the tubes of fire tube boilers and increased, as whenconstructed in accordance i with this invention the said tool can bemadevery short so as to readily pass around the bends of the water tubesof Stirling boilers and other bent tubes where the radius of the tube isnot too small, and moreover the air or other fluid passages in thehammer part y ,'liow from 'the annular space 13 around the arenot'liable to become choked and means are provided for propelling theremoved scale forward along the tube clear of the working tools and forkeeping said tools cool.

In the accompanying drawings illustrating the invention Figure l is alongitudinal elevation of a scaling tool constructed in laccordance withthis invention and repre-l sented asin operation removing the scale fromthe interior of a tube,which is also shown 'in section,I this figureshowing the -piston on its back stroke; Fig. 2 shows the =same parts asFig. 1 with the piston in its `extreme forward postion; Fig. 3 is across vsection of the tube on line X X of Fig. 2 with the scaling toolin front elevation; Fig.

4 is a cross sectional elevation of the scaling vtool taken on line Y Yof Fig. 1; Fig. 5 is a cross sectional l elevation of the same tooltaken on line Z Z of Fig. 1. A We will describe this invention asarranged to be worked by compressed air, but it will be understood thatthe same tool can also be worked by other fluid pressure as forinst-ance by steam, or water.

The piston or hammer proper is marked A. The inner casing B has its backend 1 closed and is. fitted and screwed into the open back end 2 of thevouter casing C, said .inner easing B having'an outer flange 3 'whichjoints against the back end 2 of the outer casing C. The inner. casing Bis screw threaded externally for a vshort distance along its outerperiphery from the flange 3 and the vouter casing .C is screw threadedinternally for a suiicient distance from its :back end 2 to receive thescrew threaded part of the inner casing B. The inner casing B has aprojecting tapped boss part 5 for the connection of the compressed air.supply tube ,nular passage longitudinal grooves 11,. 12,

which are continuations of the passages 8, 9, lead to the annular space13 between the in. ner casing B and the outer casing C', so that the airpasses along this annular space 13 to the fore end 14e of the innercasing B, which. latter is made somewhat shorter 'than the as to leavesutlicient space at 15 for the kair to end 14 of the inner cylinder andinto the "interior of the same. By unscrewing the inner casing B fromthe outer casing C .the grooves .10, 11, and an' passages 8, 9, can

' passage 21 which extends from the cross port 20 to the back end 422 ofthe piston. The fore end 23 of the piston shank 16 is conical orinclined asV shown so as to act upon the correspondingly inner inclinedfaces 24 of vthe series of chisel like or blunt tools y25 which arejointedly connected at 26 by the collar 27 at the front. end of theouter cylinder C and at the outer sides of their front ends they are, asin other percussive scaling toolsvof the same type, made with chisellike parts 28 or otherwise formed to 'chip oil the scale from theinterior of the tube.

In order to enable the tools 25 to be readily removed from the cylinderand changed or renewed, said tools are made, with enlarged back ends 30which engage in an internal annular groove 31 formed in the removablecollar 27 which latter is screwed on to the fore-end of the cylinder'at32.

When the scaling tool is in use the cornvpressed air passes along thepassages 8, 9,

and along the annular space 13 and through the space 15 at vthe frontend of the inner cylinder B into the interior of the same and alsopasses through the port 20 of the hammer piston shank and Vthrough thelongitudinal port to the back end 22 of the piston thereby driving the`piston and hammer shank forward, say from the `position shown in Fig. 1to the position shown in Fig. 2, so that the inclined fore-end vof thehammer shank acts upon the internallyinclined parts 24 of the tools 25driving them outwardly against the scale and chipping oli" portions ofthe same from the interior of the tube, the air exhausting through theport 20 as soon, as the-latter has passed through the cylinder neck 18.Immediately this happens the air pressure acting on the smaller area ofthe piston .17 drives the same backwardly until the port 20 enters thecylinder so that the air pressure can then pass through the port and acton the larger area of the piston and drive the same forward for anotherblow. Thus a very rapid -vibratory movement is imparted to the pistonand shank and repeated blows are delivered on the tools 25 to remove thescale in the way well known. The front portion of the hole in the neck18 of the cylinder is enlarged slightly as shown so as to form anannular exhaustv passage by which the exhaust air is directed along thepiston shank to its coned or inclined fore-end 23 and away from theacting tools 25 so as to blow the. scale forward along the'tube.

In order to edectually prevent any damage to the interior of the tube34: from which the scale is being removed, the said cross ports -20 inthe Vpiston shank 16 which regu,-

lates the air inlet to the back of the piston 17 and also the exhaust asaforesaid, are, or may be, so proportioned and arranged that the secondor inclined fore-end 23 of the piston shank makes its return strokeimmediately it has struck the incline .24 of the chisel like tools 25,so that when the impact of the blow is through the tools delivered on tothe innersurface of the scale so as to remove the same, the blow is to agreat extent spent before the chisel parts 28 of the tools strike theinterior of the tube 34 and thus any damage to the latter is etfectuallyprevented.

What we claim as our invention, and desire to secure by'Letters Patentis 1. Ina percussive tube scaling tool, the combination of a cylindercomposed of .an inner and outer casing and provided with an annularpassage between said casings, a boss provided with passages andconnected tothecylinder and adapted to be attached to a supply pipe, aneck piece secured to' the v one end of the cylinder, a collarsurrounding said neck, a reclprocatmg hollow plston conical at itsfore-end, located within said neck' and inner casing and provided withcross ports and acting as a valve, and a plurality of chipping toolshaving each an end within said collar and arranged around said pistonsubstantially as and for the purpose lherein specified.

2. In a percussive tube scaling tool, the combination of a cylindricalouter casing formed with 'a neck portion, a cylindrical inner casinglocated concentrically within the outer casing and formed in Aone with aboss to which a supply pipe may be attached, y

said boss being provided` with passages, there being an annular passagebetween said casings, a reciprocating hollow piston conical at itsfore-end located within said neck and inner casing and provided withcross ports and acting as a valve, a plurality. of pivoted and radiallymovable chipping tools arranged around said piston and a grooved collarscrewed on to said neck for retalning said tools in position,substantially as and for the purposeherein set forth. g

In testimony whereof we atlix our signatures in presence of twowitnesses.

.- GEORGE FREDRICK CLEMENTS.

Witnesses:

CHARLES BoswoR'rH KETLEY, BERTHA MATILDA DEELEY.

